This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. It is frequently hypothesized that primate cognition has evolved in response to selective pressures for the ability to process complex social information (e.g., Tomasello &Call, 1997). The social complexity hypothesis suggests that central insights into the structure and function of primate cognition will be achieved through the study of social cognition;however, few neurobehavioral studies of primate cognition have made use of social stimuli. There is a critical need for studies of social cognition in primates. Historically, one of the issues retarding the development of such studies in monkeys is the difficulty in presenting animals with experimentally-controlled social stimuli. Our objective in this project is to develop a new behavioral paradigm for studying primate social cognition that permits reliable experimental control of social stimuli by using digitally-edited video clips of monkeys interacting. We have collected a library of primate social behavior videos at the field station using monkeys in Dr. Mark Wilson's laboratory. We have filmed 14 individual monkeys engaged in a variety of social behaviors and have edited many of these clips together to make realistic artificial social interactions. A group of 6 monkeys have been successfully trained to make dominance discriminations using these video clips. A variety of probe tests have revealed that the monkeys'performance is not controlled entirely by dominance information, however, and further probes are currently being run in an effort to determine what other information the monkeys may attend to in these videos. Other probes have demonstrated that the monkeys do remember individuals seen in the videos, and their relative rank. We have discovered close parallels with human face perception in monkeys. We have successfully trained monkeys on a transitive inference task thought to be similar to dominance hierarchy learning.